C-Stack Series: What is Virtualization?
5 Analogies That Explain- What is Virtualization?
Virtualization can be a difficult topic to explain. Essentially, it’s the creation of a virtual network, storage, or server instead of a “real one.” You separate the software layer from the hardware layer, while placing a new layer between them to act as a liaison.
Explaining what virtualization is can be challenging, but we developed five analogies to help you create a better mental picture. It all starts with a flight simulator.
1. How Does Virtualization Work, and Why a Flight Simulator?
The first analogy we’ll use to explain virtualization requires a flight simulator. A flight simulator, both for regular PC games or an official training facility, is a software designed to emulate the experience of being a flight pilot. The software provides all of the systems and features of a real plane. In other words, you simulate watching the fuel gauges, the engine status, navigation, airspeed, altitude, wind speed, etc. However, no matter how real the simulation is, you are never in charge of a real airplane.
Virtualization works in the same way. When you control the software of the simulator, the software responds independently of controlling the hardware of a real airplane. With virtualization, you can interact with the software (Windows, Mac, or Linux) independent of the hardware it’s being run on. The virtual layer between the OS software and the computer hardware allows you to “trick” the computer, the same way a flight simulator gets tricked thinking it’s letting you fly a real plane.
2. What does Carpooling Have to Do with What Virtualization is?
With the flight simulator analogy, you have to assume that only one software install (Windows) is running on one piece of hardware (the PC). That means it matches one software layer with one hardware layer, which hardly seems practical.
Imagine that all software are riders, and all hardware are a type of vehicle. A motorcycle would be the equivalent of a laptop or PC. Servers are the equivalent of a car. Although each car can comfortably seat three to five riders, many cars on the road carry only one.
What is virtualization in this situation? It's like a carpool –servers, like a car, are capable of carrying higher capacity beyond a single rider. Virtualization takes the drivers (the software) from the different cars (servers), and lets them all ride in a single car. Each layer of software then operates independently of their original “car.”
3. Today’s Virtualization is Less Carpool, more SUV
A host server with virtualization, like our partner VMware, is more of an SUV with the HEMI engine. It has a powerful, high capacity, but if it only had one software inside of it, it would be the equivalent of a rider driving alone in a large SUV.
The server is powerful, and it’s capable of carrying the entire family (plus the dog). It would be a shame not to use it to its full potential. Virtualization works by tricking the SUV driver into thinking he’s only driving a smaller car. The driver (the software) thinks it’s been paired with a certain type of vehicle (hardware), even though he’s still riding the same SUV (he is, clearly, very sensitive to suggestion). VMware takes it even further by getting MORE drivers into the same SUV and telling the highly-suggestive drivers the same lie. Each individual driver thinks that they are driving their own small car and operating them of their own accord, even though they’re all still riding in the same SUV.
With virtualization, the powerful host server can house multiple instances of Windows Server, and each instance believes that they are operating on their very own host server.
4. VMware is a Bus on the Virtualization Highway
VMware takes the analogy another step further. A bus (the host server) is even more powerful than an SUV and capable of carrying more passengers. If the host hardware is even bigger and more powerful, it could house an entire bus-load of highly-suggestive passengers. Even though more than 20 or so individual riders are sitting on a bus, they all think they are driving their own small car. By doing this, you maximize the usage of your servers, using them to their full potential.
5. VMware’s High Availability Makes Virtualization like a Train
Specific to VMware, their high availability makes them the train in this prolonged vehicle analogy. A train is powerful, can take multiple cars, and the passengers can move freely between the cars without stopping the train. You can even allocate or limit specific passengers to specific parts of the train to spread them out. Likewise, VMware’s high availability allows you to move virtual software around freely without stopping any function to the hardware itself.
The Benefits of Virtualization – Transportation Analogies Aside
Virtualization is the network infrastructure of the future. It has proven, over the years, to be the most efficient way to handle enterprise infrastructure.
We can summarize the benefits of how virtualization works as follows:
- Energy efficiency
- Ease of management
- Server consolidation
- High availability
- Reduced physical footprint
- Ease of server recovery
- Better backups & restores
- Simplified DR/BC
- Lower hardware maintenance costs
- Less heat, lower cooling requirements